Ofcom fines O2 £10.5M for overcharging customers

O2 initially identified issues with its billing processes in 2011 but efforts to address them were not successful, Ofcom said, adding that over 140,000 customers were overcharged when leaving the firm between 2011 and 2019.

I remember getting a cheque from O2 for a few pound due to the overcharging a few years ago from when I was a customer with them many years ago.